Give the person the total of the bill then calculate change owing from the money they give you to pay. For example (if currency you are using is dollars and cents): The customer's bill comes to $4.73 and they give you a twenty dollar bill to pay. The change due would be $15.27. You give them their change using 1 quarter, 2 pennies, a 5 dollar bill, and a ten dollar bill. 1)Put the quarter and 2 pennies down and say "27 cents" 2)Put the 5 dollar bill down and say "plus 5 dollars is 5 dollars and 27 cents" 3)Then put down the ten dollar bill and say "plus ten dollars is $15.27" Never put the money a customer gives you to pay away before giving them their change. This will prevent them from saying they gave you more than they actually did when you give them their change (example: the customer claims they gave you $20 when in fact they only gave you $10). This will prevent arguments and you possibly unfairly losing money. Another tip is to never give change before having the money they are paying with in your hands. I used to work in the service industry and had instances when the customer claimed to have already handed the money over when they had actually put it back in their wallet without thinking. There is also a scam where someone will come into a store or a restaurant asking for change for a large bill. They are always very polite and often offer a tip to you for the favour of changing the money. They then distract you while you are getting change by chatting about another topic or about what bills they need in change. They leave without ever actually giving you the money they got change for. I have had this tried with me (once successfully) and it is suprisingly easy to be fooled. Hope that helped!